Table 2.

Pathogens, opportunistic microorganisms and faecal indicators reported from beach sand.

Cases Reported	Details
Staphylococcus aureus and MRSA Increased persistence in California, USA [48]	Found in 2.7% of the samples
Candida spp. including C. auris. increased presence with decreased precipitation (predominantly found in dry sands) in Portugal, Florida, USA and Colombia [49,50,51]	“85 of 495 samples were positive for Candida spp.” [49], “C. auris isolated from water and harsh wetlands” [50]; “Association between indicators and pathogens; C. tropicalis was the most frequent Candida spp. isolated from dry sand with an average count of 34.3 CFU/g of dry sand, followed by C. parapsilosis with 1.6 CFU/g, C. glabrata with 1.2 CFU/g and C. guilliermondii with 0.6 CFU/g” [51].
E. coli elevated numbers in water correlated with increased wave height in Lake Huron, Canada [52] and associated with wider dispersal of microbes and water releases into Lake Superior, USA [53]	“E. coli concentrations in the surface (unsaturated) sand 1 m landward of the initial shoreline (P1) were 1.23 ± 0.99 log CFU/g” [52]; “When E. coli concentrations in sand and sediment samples were converted to CFU per interstitial water, the greatest numbers of E. coli were observed in nearshore and upshore sands, followed by shoreline sands and sediment. These numbers were, on average, 63, 74, 1087, and 4982 times greater in sediment, shoreline, nearshore, and upshore sand samples, respectively, than the concentration of E. coli in lake water expressed as CFU/mL” [53].
Enterococci in mobilized sand caused a spike in water contamination with increasing wave action in Florida, USA (experimental, laboratory conditions) [54,55]	“The time duration for a certain percent die-off is inversely proportional to the solar radiation intensity. It takes 2.2 h to deactivate 90% of the total enterococci at noon time with a near maximum solar insolation of 800 W m−2“ [54]; “For trials with waves, analysis of the top and bottom layers of sediment in the ‘‘final’’ seeded sand revealed that more enterococci were removed from the top layer (78% removal and standard deviation of 17%) as compared to the bottom layer (58% removal and standard deviation of 28%) (p = 0.05, average difference between top and bottom layers = 194 CFU/g dry sand)” [55].
Helminths found in Lithuanian beach sand [41]	“The soil must not be contaminated with helminths, enteroviruses, pathogenic enterobacteria, intestinal rods.”
Hepatitis A virus (HAV) and Human Adenovirus (HadV) genetic material found in beach sand with qPCR, although viability of viral particles was not tested [56]	“HAV were detected in 6.25% (3 out of 48) and HadV were detected in 8.33% (4 out of 48) samples using qPCR. These results corroborate the reporting of sand as an independent source of GI illness.”